1. Field of the Invention
The present invention relates generally to the fields of developmental biology, cell biology and molecular biology. More particularly, it relates the muscle cell fusion activity of the Myomaker protein.
2. Description of Related Art
Myoblast fusion is a complex and tightly controlled process required for the formation of skeletal muscle fibers (Chen and Olson, 2005). The fusion process must be highly cell type-specific to ensure that fusogenic myoblasts do not form syncytia with non-muscle cell types. While the transcriptional mechanisms governing skeletal muscle development have been elucidated in detail (Bentzinger et al., 2012; Berkes and Tapscott, 2005; Buckingham 2006; Kang and Krauss, 2010), the mechanisms that coordinate myoblast fusion remain poorly understood, and no muscle-specific protein that directly regulates myoblast fusion has been identified in any organism (Abmayr & Pavlath, 2012; Rochlin et al., 2010). In contrast, numerous proteins involved in cell-cell adhesion and actin dynamics have been implicated in myoblast fusion (Charrasse et al., 2007; Charrasse et al., 2002; Schwander et al., 2003; Griffinet et al., 2009; Yagami-Hiromasa et al., 1995). However, none of these proteins are muscle-specific, necessary and sufficient for mammalian myoblast fusion, suggesting that muscle-specific components of this process remain to be discovered.